The pregnant woman was covered with blood, and Steve Hensley, the police chief in Fort Mitchell, Ky., could scarcely believe her tale.

Sarah Brady, 26, said she had been lured to an apartment in Fort Mitchell that was outfitted with surgical tools and a nursery. There, a woman who had promised to hand over a mis-addressed baby present attacked Brady in an attempt to extract her unborn child by Caesarean section.

Instead, Brady, who was nine months pregnant, fought back and fatally stabbed her assailant, unemployed nanny Katie Smith, 22. Police say Smith had fooled her family into thinking she was pregnant by wearing padded maternity clothes and had planned to steal Brady's fetus - and presumably kill Brady - as the final act in a gruesome ruse.

"It's the most bizarre case I've seen in 22 years" of police work, Hensley says of the attack, which occurred Feb 17.

The incident came two months after a similar attack in Missouri in which the mother was killed and her baby survived. Such attacks on pregnant women are rare, but they have become increasingly common across the nation in recent years: The attack on Brady was the third such assault on an expectant mother since December 2003 and the ninth since 1987, according to statistics compiled by the National Center for Missing and Exploited Children in Alexandria, Va.

Seven of the nine pregnant women who were attacked died; seven of the nine babies survived. (Brady's attorneys in Covington, Ky., did not immediately return phone calls; the Associated Press has reported that she gave birth to a healthy baby girl, McKaila Grace Hatton, on March 16.)

Caesarean kidnappings represent a small fraction of the 232 infant abductions by non-family members since 1983, according to the center. But such kidnappings - along with those of infants from public places such as shopping malls - have increased as thefts of newborns from hospitals have declined, says Cathy Nahirny, a supervisor at the center.

She says improvements in security at hospital maternity wards have led to forms of kidnapping that reflect the desperation and the creativity of those determined to steal children.

Although "it's assumed that (the perpetrators) must be delusional," Nahirny says, "they (also) are very organized and quite rational. They follow a predictable pattern."

The assailants in all nine cases were women, but they had help from two men in one instance and from another woman in another.

The Kentucky case had several elements in common with earlier Caesarean kidnappings.

Smith, who was not married, carried around an ultrasound picture of someone else's unborn twins and told family members that she had given birth previously but that the babies had died. Hensley says he's found no evidence Smith ever gave birth.

Smith apparently selected Brady as her victim by scanning an online baby registry. Smith then lured the expectant mother to her apartment by claiming that a baby present meant for Brady mistakenly had been delivered there.

Earlier Caesarean kidnappings followed a similar pattern.

Last December, 23-year-old Bobbie Jo Stinnett of Skidmore, Mo., was killed and her 8-month-old fetus was removed, allegedly by Lisa Montgomery.

Montgomery, 37, of Melvern, Kan., had posed as an expectant mother before the crime and then showed the baby boy off as her own to neighbors and family members, including her unsuspecting husband, the FBI says. She had won her victim's confidence by posing in e-mails as a fellow dog fancier, according to the FBI. Montgomery is scheduled to stand trial in the murder in April 2006.

Previous kidnappings by Caesarean have occurred in Oklahoma in 2003, Ohio in 2000, California in 1998, Alabama in 1996, Illinois in 1995, Texas in 1992 and New Mexico in 1987.

In the New Mexico case, Darci Pierce, a 19-year-old married woman, abducted a pregnant woman from outside a clinic in Albuquerque, choked her into unconsciousness, then used car keys to cut into the woman and deliver a baby girl. Pierce was caught when she sought a birth certificate at a local hospital and an exam showed she had not recently delivered.

It was the first recorded case of what a July 2002 study in the Journal of Forensic Sciences would call "newborn kidnapping by Caesarean section." Ann Burgess, a professor of nursing at Boston College and the study's lead author, says the women behind such attacks have a "childbearing fantasy" but are "cold, calculating and extremely self-centered."

Pierce was found guilty but mentally ill and was sentenced to a minimum of 30 years in prison.

Of the six other alleged assailants besides Pierce, Smith and Montgomery, two received prison terms, two committed suicide, one was placed on probation and another was found incompetent to stand trial.

Since 1983, there have been 116 thefts of infants younger than 6 months by non-family members from hospitals or birthing centers, according to statistics by the National Center for Missing and Exploited Children. The center trains police and social services workers to prevent child abductions.

Such abductions from hospitals have declined since 1991, when 11 of the 17 abductions that year were from hospitals. In 2003 and 2004, a total of 12 abductions were recorded by the center. Three were from hospitals.